diff -u b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
--- b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
+++ b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
@@ -215,6 +215,8 @@
 
     if (!empty($items)) {
       \Drupal::service('photoswipe.assets_manager')->attach($elements);
+      $elements['#prefix'] = '<div class="photoswipe-gallery">';
+      $elements['#suffix'] = '</div>';
     }
 
     foreach ($items as $delta => $item) {